The next ST7 sneak peek is curve driven assembly patterns. In ST7 you'll be able to pattern components in an assembly using sketches, curves, or the assembly as input. You'll also be able to pattern in a second direction (presumably perpendicular to the curve). Another goodie coming with this enhancement is the ability to see a preview of your pattern before you commit to it.
Are you already plotting how you're going to use this one? This looks like a nice enhancement, and I'm sure there are a few people wiping a little drool off their chins.